This book constitutes the thoroughly refereed proceedings of the 16th National Conference, NASAC 2017, held in Harbin, China, in November 2017, and the 17th National Conference, NASAC 2018, held in Shenzhen, China, in November 2018. The 6 revised selected papers were selected from 17 submissions for NASAC 2017, and 5 revised selected papers were selected from 20 submissions for NASAC 2018. The papers focus on all aspects of software engineering, e.g. requirements engineering, software methodologies, software analytics, software testing and evolution, and empirical studies.